Engine no-start, need help.

[Holcono]

I have a 2001 Ford Explorer, 4WD. 4.0l.

I really like this vehicle, but unfortunately I'm an automotive idiot. I understand concepts, but have very little practical experience repairing a vehicle, or troubleshooting. I've decided it's time to learn, so I'm hoping I can pick some of your brains and maybe figure out how to do something on my own!

About 3 months ago, it started getting very cold in Dayton, Ohio. My truck started having lots of trouble started. It would turn over a bunch then start. Then turn off. Then I'd start it again. Second time was usually the charm.

Well when it warmed up for a couple of weeks, the problem went away. I figured it must just not like cold starts. When it dropped below zero, I couldn't start it at all.

Now, it won't start no matter what the temperature is. I tried the ether test, and it doesn't pop. I tried to easy stuff. I bypassed the inertia switch, no go. I replaced the cam sensor. No go.

When I hooked the voltmeter up to the cam sensor after leaving the truck alone for a day, it would try to start, the Cam sensor registered .2V then nothing. Consecutive attempts to start show no reading at all on the volt meter, but the Cam sensor replacement didn't do anything to fix it.

I acknowledge that you guys are probably bombarded by people who want help to save some money. But I seriously want to learn this. No shade tree mechanics in this area seem to need money, as they're all pretty busy. So my options are to use this as a learning experience and see if anyone here might be able to give me some trouble shooting tips, or take it to a professional and waste money and learn nothing.

Hopefully someone here might be charitable with their knowledge I am new to your community, but I'd definitely going to be a repeat flyer, as I intend to learn a lot and this truck is going old enough it's probably going to provide lots of subject matter.

 

[2000StreetRod]

which engine?

If the SOHC V6 this thread may help: Ford Explorer Engine No Start Procedure

Welcome to the forum!

 

[Kiliona]

Hello there!

First things first, throwing random parts at a problem and hoping it goes away is a very quick way to go broke . not to be rude. Don't replace anything until you know it's broken!

Here's a crash course in no-start problems.
An engine needs fuel, spark, and air to start. so there's three different ways to go about testing it. and three different areas to test.

By checking the cam sensor, you're testing spark (ignition timing), not to makwe sure it's there, but to make sure it's there at the right times. Now the bad news is, a bad cam sensor wouldn't case a nostart issue. If you unplug the cam sensor your computer will know it and substitute in a known value and take an educated guess at where your cams at. It'll probably just look at your crankshaft position sensor adn figure it out from there. it might take twice as long to start (it has to wait until piston 1 hits TDC to know when to spark) but it WILL start. It might start and go into limp mode - no power stays in 2nd or third gear, knows it has a problem so it just tries to get you home - but it will start.

To start testing your ignition at a very basic level, pull off a spark plug wire and plug, set the ground electrode on the spark plug on a good ground (bare piece of metal connected to engine or body, also if you can hold it with something plastic so you don't shock yourself, won't damage you but will sting) plug the spark plug boot onto it, have a friend crank it over, watch to see if electricity flows between the electrodes. If you're alone you can also jump the S terminal on the starter solenoid to crank it from under the hood. Alright, check a few that are easy to get to, if you see sparks you know you have spark. You don't know you're timings correct, but if you dont/havent had a check engine light chances are your timings fine on your computer controlled car.

Next is fuel, this is what I think is probably wrong, fuel. Your symptoms sound to me like a bad fuel pump. The way to make SURE that the fuel pump is the issue, is go buy a 20 dollar fuel pressure gauge from any auto part store and hook it up. Your fuel pressure should read... 40-60 psi? on a second gen im not sure. And it should hold the pressure, it shouldn't leak and lose pressure, watch it for 30 seconds- 5 minutes and make sure you aren't losing pressure. If you are, you have a leaky injector, a bad fuel pressure regulator (are second gens return type?) or a hole somewhere. If your fuel pressure doesn't build to proper psi, you can be pretty sure it's your fuel pump. It's gotten old and lazy and can't give you enough fuel.

The backyard way of testing this with no tools.
When you turn the key on (not to crank the starter, but to the on position where the dash lights up and ignition turns on) you should hear a wine coming from your fuel tank. Your fuel pump should kick on for 2-3 seconds every time the key is turned to on. You should be able to hear it from the cab, if not, sit next to the tank (first gens it's by the rear passenger door outside the cab, probably same on second) and have a friend cycle the key. you should hear a whining sound.

When you cycle the key it turns the fuel pump on, cycle the key 5 times THEN try to start the car, if it starts, that most likely means your fuel pump is weak and it took it turning over 5 times to build proper fuel pressure to start the car. that's another way to tell if it's a fuel pump.

third, air. Doing a compression test is the easiest way to do this, and this'll tell you all about what shape your engines in on the inside. Do the fuel tests firsts if you aren't comfortable with a compression test.

OH and some advice, if at any point you need to remove a fuel line, to relieve fuel pressure quickly and painlessly unplug your inertia switch (fuel pump shutoff switch) and try and start the car for 10-20 seconds. This'll use up the fuel pressure in the lines.

This stuff interests me, so writing up stuff like this is a good way for me to review, i enjoy doing it, I just hope someone benefits from it .

 

[Holcono]

Thanks for the responses. I'll do some tests then and report my findings! Tried cycling the key a few times, it didn't start.

I had replaced the Cam sensor because I listened to an Autozone sales person, who told me if the voltage wasn't registering through it, that it was bad.

Should it be the fuel pump, should I even bother trying to learn how to replace it myself, or accept defeat until I've learned more basic things first? haha

 

[2000StreetRod]

Ohv v6?

I still don't know which engine you have. If you don't know look at the 8th digit in your VIN. An "X" is the OHV V6 and an "E" is the SOHC V6. From what I've read on the forum the V8 and the OHV V6 will start and run (although poorly) with a failed synchronizer (camshaft position sensor) but the SOHC V6 won't usually start with a failed camshaft position sensor. For the SOHC V6 the only function of the camshaft position sensor is to notify the PCM if cylinder 1 is on the compression stroke or the exhaust stroke. All fuel injection and ignition timing is based on the crankshaft position sensor. According to the PCM source code I've read there are provisions for the timing to continue if the camshaft position sensor fails after the engine has started - and limited provisions for even the crankshaft position sensor failing.

I agree that determining what has failed before replacing parts is the best approach for learning about how the vehicle functions and saves time and money in the long run. Most basic (but adequate) test tools are fairly inexpensive and usually after being acquired can be used on any vehicle. I suggest purchasing test tools as you need them unless you get them as gifts or there is a special sale. I usually have tools on my Christmas wish list.

There is a lot of information on the forum and use of the search function can be productive. There are also many members who have many years of experience who will chime in to give you help. If you have tools, patience, and a place to work there's not much you can't do except for machine work.

 

[Holcono]

Oh I apologize, it's a V6.

 

[Explorer0204]

Oh I apologize, it's a V6.

We know that.. But what we need to know is which one.
I don't know too much about 2nd gens but they came with both an OHV v6 and a SOHC v6
Overhead valve
Single overhead cam

The difference is that the overhead valve one utilizes what are called pushrods to move the valves in the head. The camshaft is in the block of the engine on these.

The single overhead cam engines use a camshaft in the valve cover area of the engine over both banks of 3 cylinders. Timing chains then run from the crankshaft to those camshafts to press the valves down during operation.

Hope this makes sense if not I can explain more thoroughly. I don't know what your knowledge is of engines.

Also, look under the hood to figure out which one you have..